World of Warcraft FPS issue

[boxlinger]

So I recently transfered a character to a high populated realm after being on a low populated realm for almost 7 years. The first thing I noticed is my FPS dropped a TON. I instantly made a new character. I wasn't in a high populated area at all and my FPS was at 1 for a long time. So thats my problem and I want to know if their is a way I can increase my FPS without buying a new machine. I had all my settings on low, and just everything bad in general. I found a few other things on the subject but I'm a complete noob when it comes to computer speak. So could you put everything in noob speak, that would be greatly appreciated, thanks.

 

[Huntn]

You have an older Mac? On servers most slowdown is seen in heavily populated towns. Try turn off shading and anti-aliasing, lower view distance.

 

[boxlinger]

Yeah, I have an 07 iMac. I tried all that still no luck I read somewhere about increasing GPU or assigning it RAM. Would this do anything, if so, how do I do it?